display all the ideas for this combination of philosophers
8 ideas
16295 | Tarski proved that truth cannot be defined from within a given theory [Tarski, by Halbach] |
Full Idea: Tarski's Theorem states that under fairly generally applicable conditions, the assumption that there is a definition of truth within a given theory for the language of that same theory leads to a contradiction. | |
From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Volker Halbach - Axiomatic Theories of Truth 1 | |
A reaction: That might leave room for a definition outside the given theory. I take the main motivation for the axiomatic approach to be a desire to get a theory of truth within the given theory, where Tarski's Theorem says traditional approaches are just wrong. |
15342 | Tarski proved that any reasonably expressive language suffers from the liar paradox [Tarski, by Horsten] |
Full Idea: Tarski's Theorem on the undefinability of truth says in a language sufficiently rich to talk about itself (which Gödel proved possible, via coding) the liar paradox can be carried out. | |
From: report of Alfred Tarski (The Concept of Truth for Formalized Languages [1933]) by Leon Horsten - The Tarskian Turn 02.2 | |
A reaction: The point is that truth is formally indefinable if it leads inescapably to contradiction, which the liar paradox does. This theorem is the motivation for all modern attempts to give a rigorous account of truth. |
19069 | 'True sentence' has no use consistent with logic and ordinary language, so definition seems hopeless [Tarski] |
Full Idea: The possibility of a consistent use of 'true sentence' which is in harmony with the laws of logic and the spirit of everyday language seems to be very questionable, so the same doubt attaches to the possibility of constructing a correct definition. | |
From: Alfred Tarski (The Concept of Truth for Formalized Languages [1933], §1) | |
A reaction: This is often cited as Tarski having conclusively proved that 'true' cannot be defined from within a language, but his language here is much more circumspect. Modern critics say the claim depends entirely on classical logic. |
10153 | In everyday language, truth seems indefinable, inconsistent, and illogical [Tarski] |
Full Idea: In everyday language it seems impossible to define the notion of truth or even to use this notion in a consistent manner and in agreement with the laws of logic. | |
From: Alfred Tarski (works [1936]), quoted by Feferman / Feferman - Alfred Tarski: life and logic Int III | |
A reaction: [1935] See Logic|Theory of Logic|Semantics of Logic for Tarski's approach to truth. |
19177 | A definition of truth should be materially adequate and formally correct [Tarski] |
Full Idea: The main problem of the notion of truth is to give a satisfactory definition which is materially adequate and formally correct. | |
From: Alfred Tarski (The Semantic Conception of Truth [1944], 01) | |
A reaction: That is, I take it, that it covers all cases of being true and failing to be true, and it fits in with the logic. The logic is explicitly classical logic, and he is not aiming to give the 'nature' or natural language understanding of the concept. |
19178 | Definitions of truth should not introduce a new version of the concept, but capture the old one [Tarski] |
Full Idea: The desired definition of truth does not aim to specify the meaning of a familiar word used to denote a novel notion; on the contrary, it aims to catch hold of the actual meaning of an old notion. | |
From: Alfred Tarski (The Semantic Conception of Truth [1944], 01) | |
A reaction: Tarski refers back to Aristotle for an account of the 'old notion'. To many the definition of Tarski looks very weird, so it is important to see that he is trying to capture the original concept. |
19186 | A rigorous definition of truth is only possible in an exactly specified language [Tarski] |
Full Idea: The problem of the definition of truth obtains a precise meaning and can be solved in a rigorous way only for those languages whose structure has been exactly specified. | |
From: Alfred Tarski (The Semantic Conception of Truth [1944], 06) | |
A reaction: Taski has just stated how to exactly specify the structure of a language. He says definition can only be vague and approximate for natural languages. (The usual criticism of the correspondence theory is its vagueness). |
19194 | We may eventually need to split the word 'true' into several less ambiguous terms [Tarski] |
Full Idea: A time may come when we find ourselves confronted with several incompatible, but equally clear and precise, conceptions of truth. It will then become necessary to abandon the ambiguous usage of the word 'true', and introduce several terms instead. | |
From: Alfred Tarski (The Semantic Conception of Truth [1944], 14) | |
A reaction: There may be a whiff of the pragmatic attitude to truth here, though that view is not necessarily pluralist. Analytic philosophy needs much more splitting of difficult terms into several more focused terms. |